With the development of urbanization, urban population increases rapidly, and China's large and medium-sized cities face increasingly severe traffic pressure. In some large cities, traffic jam at rush hours seriously blocks the sustainable development of the cities. One effective measure to solve the traffic jam at rush hours is to encourage city residents to take public buses; however, some bus routes short of transportation capacity at rush hours limit the enthusiasm of city residents taking public buses. The best measure to solve the transportation capacity shortage at rush hours is to improve the transportation capacity, however, simply increasing the number of public buses for hot routes will result in redundant transportation capacity at non-rush hours, this is neither economical nor green; therefore, a concept of intelligent scheduling for public transportation appears accordingly. The intelligent scheduling for public transportation is to gather statistics on the number of passengers getting on, the number of passengers getting off and the total number of passengers onboard for each bus of each route through a terminal mounted on each bus, so as to monitor the passenger load condition of each bus route at each time period. In addition, the intelligent scheduling for public transportation also can perform deeper data mining using the history data of passenger flow about getting on and getting off of each bus stop at each time period, to provide a basis for planning a reasonable efficient bus route. Therefore, as the most important part of an intelligent scheduling system for public transportation, the accurate statistics on the number of bus passengers is the key to realize the intelligent scheduling system for public transportation.
Traditional passenger flow statistics method is to gather statistics using manual detection, or using contact devices such as bus money-box and card swiping machine. Herein, for the method adopting manual statistics to obtain the passenger flow data, although the accuracy can meet the requirement, a lot of labor forces and financial forces are consumed, the cost is high and the timeliness is poor. A secondary method is using an infrared detection system, although the infrared detection system can realize the statistics on the numbers of passengers getting on and getting off simultaneously, the infrared device is easy to be interfered by external factors, for example, error statistics probably may be caused if passengers pass through continuously or stay for a long time, the infrared detection system cannot meet the accuracy requirement of passenger number statistics for the intelligent scheduling system for public transportation. Meanwhile, since the infrared system can only realize the statistics of the passengers passing through the bus door and cannot judge the movement direction of the passengers, that is, the infrared system cannot realize the double-direction counting of passengers of a single bus door; therefore, the infrared system is not applicable to a rapid transport system which makes no distinction between an entrance door and an exit door. As the coverage of the rapid transport system becomes wider and wider, the detection measure using the infrared ray to count the number of bus passengers has an increasingly lower applicability.